DRS, Barry Smith and Paul Kornblith of NINCDS, Surgical Neurology Branch have begun using a computerized light microscope to do in-vitro cytotoxicity studies and computerized electron scanning microscope to do chemotherapeutic cell monphology studies. Our laboratory has extensivily expanded the computer (a Data General Nova) so that the system will be more user friendly and much more complicated analysis may be done. Several design flaws have been discovered and corrected. A separate printer channel has been added and two high speed CRT's have been added. Momory has been expanded to the maximum so that two tasks may be run concurrently. At present only one level of thresholding may be done and additional hardware has been ordered to allow 256 levels of thresholding and display. The electron microscope interface will be replaced with a more general purpose one that will be connected to the SEM and their 200 kv STEM. An interface is also planned for the energy dispensive x-ray analzer allowing elemental images to be collected. Most of the software will have to be rewritten to handle the new hardware. The cell counting is now being done on a production basis and the cell monphology studies are being done on a routine basis.